It is stunningly NOT OBVIOUS from Microsoft's Web Site, but if you want to flash the firmware on your XBox Wireless Adapter MN-740, you need to download the Microsoft Broadband Networking super-update and it will find the adapter on your network automatically.
If you've flashed it before with the stand-alone updater that was specific to this adapter, you'll notice that this procedure is different and a little obtuse. However, it does work well.
Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. I am a failed stand-up comic, a cornrower, and a book author.
Disclaimer: The opinions expressed herein are my own personal opinions and do not represent my employer's view in any way.